Door mechanism

ABSTRACT

A door mechanism including self-acting latching means operatively holding the door closed and including a latch release member selectively moveable from a neutral position to a release position freeing the door for opening. Locking means act to secure the latched door by preventing release actuation of the latching means and including a lock drive member selectively moveable between locked and unlocked positions. The latch release member has a path of travel extending between said release position and a door secure position, said neutral position being in an intermediate part of said path. The release member and the lock drive member are coupled by motion transmitting means including a first formation on one of said members co-acting via a connecting means with a second formation on the other of said members to shift the lock drive member to the locked position on movement of the release member from its neutral position to its door secure position.

BACKGROUND OF THE INVENTION

This invention relates to latching and locking mechanisms for doors ofpassenger vehicles.

Vehicle doors are commonly provided with interior and exterior doorhandles operable from the inside or the outside of the vehiclerespectively to release latching means of the door for opening it.Provisions are also made for locking the door to resist unauthorisedaccess by locking means acting to disable or block the latch mechanismto prevent the door being freed when closed. Even if the locking meansis power operable, for example as part of a central door locking system,provisions will be made on at least some of the doors for manual lockingand unlocking at least from the vehicle interior is. This commonlyprovided by a manual push-pull button or the like, typically a cillbutton, separate from the interior door handle which adds to the costand complication of the door mechanism, and may also involve additionalcosts in terms of layout to suit the mechanism to particular styles ofdoor, and in terms of making the mechanism tamper-resistant foreffectively deterring attempted theft of the vehicle or its contents.

SUMMARY OF THE INVENTION

According to the invention there is provided a vehicle door mechanismincluding self-acting latching means operatively holding the door closedand including a latch release member selectively moveable from a neutralposition to a release position freeing the door for opening. Themechanism further includes locking means acting to secure the latcheddoor by preventing release actuation of the latching means and includinga lock drive member selectively movable between locked and unlockedpositions. The latch release member has a path of travel extendingbetween the release position and a door secure position, said neutralposition being in an intermediate part of the path. The release memberand the lock drive member are coupled by motion transmitting meansincluding a first formation on one of the members co-acting via aconnecting means with a second formation on the other of the members toshift the lock drive member to the locked position on movement of therelease member from its neutral position to its door secure position.Preferably the connecting means is one or both of a link or a resilientconnection.

Preferably where a resilient connection is provided, the resilientconnection acts in compression and is arranged to reach a state ofmaximum compression during at least part of the operation of the lockingmechanism. The resilient means can be a spring.

Preferably the spring is a helically wound spring that becomes coilbound during at least part of the operation of locking the mechanism.

Preferably resilient means acts between the members to ensure the lockdrive member returns to its unlocked position on return movement of therelease member from the door secure position to or beyond the neutralposition. The resilient means permits travel of the release member toits release position but urging or contributing to the urging of themember from that position to the neutral position.

Conveniently either or both of the latch release and lock drive membersare bell crank or other levers which may be fulcrumed about separateparallel axes or, possibly, fulcrumed for movement about a common axis.

The latch release member will typically be connected by a linkage to aninterior handle of the door so that the latter serves both to open thedoor and for its locking and unlocking.

Embodiments of the invention are now more particularly described by wayof example and with reference to the accompanying drawings, wherein;

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a side elevation of a first embodiment of themechanism of the present invention in a locked/latched condition.

FIG. 2 illustrates a side elevation of a first embodiment of themechanism of the present invention in an unlocked/latched condition.

FIG. 3 illustrates a side elevation of a first embodiment of themechanism of the present invention in an unlocked/unlatched condition.

FIG. 4 illustrates a side elevation of a second embodiment of themechanism of the present invention in a locked/latched condition.

FIG. 5 illustrates a side elevation of a second embodiment of themechanism of the present invention in an unlocked/latched condition.

FIG. 6 illustrates a side elevation of a second embodiment of themechanism of the present invention in an unlocked/unlatched condition.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring firstly to FIGS. 1 to 3, the embodiment there shown in part isa vehicle door locking and latching mechanism.

Self-acting latching means includes a rotating claw or other latchco-acting with a bolt or striker on the door post in use and retained infully closed and first safety conditions by, in the case of the claw, aco-acting pawl. The pawl is linked in turn to a latch release member, inthis example a release lever 10 having a fulcrum pivot at 12. One arm 14of lever 10 is linked to a manually operable interior handle of thedoor.

A second arm 16 includes a formation in the form of a first pin 20.

A third arm 18 acts to release the above mentioned pawl.

The locking means of the mechanism includes a bell crank lock drivelever 22 fulcrumed about a pivot axis 24 in spaced parallel relationshipto axis 12.

Lever 22 is angularly displaceable between locked and unlocked positionsdetermined respectively by fixed upper and lower stops which are abuttedby opposite sides of a first arm 30 of lever 22 (see FIGS. 1 and 2respectively).

First arm 30 operates to effect locking and unlocking of the door in amanner well known in the art.

A second arm 32 of said lever 22 has a slot 34 through which a secondpin 35 extends. Second pin 35 is mounted on link 37, the lower end ofwhich is pivoted on the first pin 20. It can be seen that the lower edge39 of slot 34 forms a formation which co-acts with first pin 20 via link37 to limit travel of release lever 10, clockwise as viewed in thedrawings, but permitting substantial movement of lever 10 in theopposition direction relative to lever 22.

A helically wound wire torsion spring 36 is located around pivot axis24, bearing at one end against stop 41 on lever 22 and at the other endagainst second pin 35, so as to resiliently urge second pin 35 towardsedge 39 of slot 34.

Drive lever 22 is provided with an over center spring which urges itinto abutment with one of the stops 26, 28 once it has passed overcenter between them so that the locking means will not be displaced froma locked or unlocked condition until appreciable operating force isapplied.

The sequence of operation of the above mechanism is as follows:

In FIG. 1 release lever 10 has been shifted by means of inside doorhandle to its extreme clockwise position as viewed in the drawings, thisbeing its door secure position. Its movement in this direction drawslock drive lever 22 positively to its locked position against upper stop26 by first pin 20 acting on link 37 to engage second pin 35 with edge39 of slot 34. This leaves the door latched and locked.

FIG. 2 shows release lever 10 shifted counter-clockwise to anintermediate neutral position. This effects unlocking, but notunlatching of the door, as the movement of link 37 substantiallyvertically upwards causes torsion spring 36 to drive lever 22counter-clockwise via stop 41. The spring is strong enough to overcomethe retaining force of the over-center spring, allowing arm 30 of lever22 to move until it abuts the lower stop 28.

To open the door the inside handle is used to shift release lever 10 toits extreme counter-clockwise position shown in FIG. 3 which will freethe pawl from the claw allowing the door to unlatch for opening. Thismotion of lever 10 is reacted against by spring 36, while the second pin35 moves through slot 34 and the lock drive lever 22 therefore remainsundisturbed against stop 28. Once unlatched the interior door handlewill be released and spring 36 urges or assists in urging lever 10 backas far as its neutral position, as illustrated in FIG. 2.

As there is no separate sill button or equivalent for effecting manuallocking and unlocking of the door from the inside of the vehicle, onlyone linking connection to lever 10 is needed from the single interiordoor handle for effecting both functions with considerablesimplification in production and assembly.

Furthermore, the interior door handle is usually remote from thevulnerable window opening of the door unlike the conventional sillbutton which may be accessed by “fishing” if the window is left, or isforced, slightly open. The door handle can be positioned, eg in a doorrecess and shaped for maximum deterrence of tampering from the vehicleexterior.

FIGS. 4, 5 and 6 illustrate a second embodiment of the invention inwhich the arrangement and action of most of the operating parts of themechanism and their mounting in the door are not shown for clarity.

Latch release lever 110 has a fulcrum pivot at 112. One arm 114 of lever110 is linked to manually operable interior door handle of the door. Afurther arm 118 acts to release a pawl and claw mechanism. Arm 118further includes a formation in the form of a first pin 120.

A locking means of the mechanism includes a lock drive lever 122fulcrumed about a pivot axis 124 in spaced parallel relationship to axis112.

Lever 122 is angularly displaceable between locked and unlockedpositions determined respectively by fixed upper and lower stops whichare abutted by opposite sides of arm 130 of lever 122.

Arm 130 operates to effect locking and unlocking of the door in a mannerwell known in the art.

Arm 130 includes a formation in the form of a second pin 150 whichco-acts with first pin 120 via spring 137 to restrict travel of releaselever 110 clockwise as viewed in the drawings, but to permit substantialmovement of lever 110 in the opposite direction relative to lever 122.

Drive lever 122 is provided with an over center spring which urges itinto abutment with one or other of the upper and lower stops once it haspassed over center between them so that the locking means will not bedisplaced from the locked or unlocked condition until appreciableoperating force is applied.

Spring 137 includes end hooks 137A, 137B which engage first pin 120 andsecond pin 150 respectively. Spring 137 is in a coil bound condition asshown in FIGS. 4 and 5 and in an extended position as shown in FIG. 6.The term coil bound refers to a tension or compression spring in whichsuccessive coils of the spring contact each other.

The sequence of operation of the above mechanism is as follows:

In FIG. 4 release lever 110 has been shifted by means of inside doorhandle to its extreme clockwise position as viewed in the drawings, thisbeing its door secure position. Its movement in this direction causesspring 137 to push lock lever 122 to its locked position against itsupper stop. This leaves the door latched and locked.

FIG. 5 shows release lever 110 shifted counter-clockwise to anintermediate neutral position. This effects unlocking, but notunlatching of the door as the movement of pin 120 substantiallyvertically downwards causes spring 137 to pull lever 122counter-clockwise to its unlocked position, spring 137 being strongenough to overcome the retaining force of the over center spring,allowing arm 130 of lever 122 to move until it abuts the lower stop (notshown).

To open the door the inside handle is used to shift release lever 110 toits extreme counter-clockwise position shown in FIG. 6 which will freethe pawl from the claw allowing the door to unlatch for opening. Thismotion of lever 110 cause extension of spring 137 whilst the lever 122remains undisturbed against its lower stop. Once unlatched the interiordoor handle will be released and spring 137 will return to the positionas shown in FIG. 5.

In particular it is not necessary that spring 137 is coil bound when inthe position as shown in FIGS. 4 or 5. The mechanism will functioncorrectly provided the following two conditions are met:

a) When release lever 110 is moved from its position as shown in FIG. 4to the position of FIG. 5 the tension in spring 137 is sufficient toovercome the over center spring on lever 122 resulting in lever 122moving from the position as shown in FIG. 4 to the position as shown inFIG. 5.

b) When lever 110 moves from the position shown FIG. 5 to the positionshown in FIG. 4 the compressive forces in spring 137 are sufficient toovercome the over center spring on lever 122 and move lever 122 from theposition as shown in FIG. 5 to the position as shown in FIG. 4.

It can be particularly advantageous that spring 137 becomes coil boundat some stage during locking of the door, though as stated above thespring need not necessarily be coil bound when the door is in the lockedand latched position or alternatively when the door is in the unlockedand latched condition.

Advantageously it can be seen that pins 120 and 150 and spring 137 ofthe second embodiment fulfil the function of pins 20 and 35 slot 34 andspring 36 of the first embodiment. Thus these components of the secondembodiment are fewer in number and easier to manufacture than theequivalent components of the first embodiment.

The foregoing description is only exemplary of the principles of theinvention. Many modifications and variations of the present inventionare possible in light of the above teachings. The preferred embodimentsof this invention have been disclosed, however, so that one of ordinaryskill in the art would recognize that certain modifications would comewithin the scope of this invention. It is, therefore, to be understoodthat within the scope of the appended claims, the invention may bepracticed otherwise than as specially described. For that reason thefollowing claims should be studied to determine the true scope andcontent of this invention.

What is claimed is:
 1. A door latching and locking mechanism comprising:a latch release member operatively able to hold a door closed having apath of travel extending between a door secure position and a releaseposition and being selectively moveable from an intermediate neutralposition to said release position to open said door; a lock drive memberselectively moveable between a locked position and an unlocked positionacting to secure said door by preventing release actuation of said latchrelease member; a motion transmitter to couple said latch release memberand said lock drive member including a first formation on one of saidmembers co-acting with a second formation on the other of said membersby a connector to shift said lock drive member to said locked positionon movement of said latch release member from said neutral position tosaid door secure position; and a resilient member acting between saidlatch release member and said lock drive member to ensure said lockdrive member returns to said unlocked position on return movement ofsaid latch release member from said door secure position to or beyondsaid neutral position and permitting travel of said latch release memberto said release position but urging said latch release member from saidrelease position to said neutral position.
 2. The door mechanism asrecited in claim 1 wherein said connector is a link.
 3. The doormechanism as recited in claim 2 wherein said link is pivotally mountedon said latch release member.
 4. The door mechanism as recited in claim2 wherein a lost motion connection exists between said link and saidlock drive member.
 5. The door mechanism as recited in claim 2 whereinsaid resilient member biases said link into engagement with said firstformation and said second formation.
 6. The door mechanism as recited inclaim 5 wherein said resilient member is mounted on said lock drivemember.
 7. The door mechanism as recited in claim 1 wherein saidconnector is said resilient means.
 8. The door mechanism as recited inclaim 7 wherein said resilient member acts in compression and tensionduring a cycle of moving said lock drive member from said lockedposition to said unlocked position and back to said locked position. 9.The door mechanism as recited in claim 7 wherein said resilient memberis arranged to reach a state of maximum compression during at least partof the operation of said locking mechanism.
 10. The door mechanism asrecited in claim 7 wherein said resilient member is a helically woundspring.
 11. The door mechanism as recited in claim 10 wherein saidhelically wound spring becomes coil-bound during at least part of thecycle.
 12. The door mechanism as recited in claim 1 wherein both saidrelease member and said lock drive member are levers fulcrumed formovement about parallel axes.
 13. The door mechanism as recited in claim1 wherein both said release member and said lock drive member are leversfulcrumed for movement about a common axis.